A next generation mobile communication system is developing so as to efficiently provide a high quality multimedia and various future technical services and to improve a transmission capacity through an efficient wireless transmitting technology.
Recently, the mobile communication system develops so as to have a structure in that an RF (radio frequency) transceiver having multiple antennas and a power amplifier are separated from a baseband modem and one or multiple RF units are located in remote site to increase a transmission efficiency and apply various wireless transmission technology.
Nevertheless, a bit resolution that the mobile communication systems use is not a problem in a current LTE standard, it may act as a problem in the future mobile communication technology which demands higher modulation efficiency. This is because a cell radius in a future mobile communication structure such as a Femto base station is getting smaller and transmission rates are getting higher as the cell radius get smaller. In order to support the modulation method having a high modulation factor, higher bit resolution of the base band signal is required.
A related art of the present invention is disclosed in Korean Patent Application Unexamined Publication No. 10-2011-0030474 (titled as compression of baseband signals in base transceiver system, published on Mar. 23, 2011). Korean Patent Application Unexamined Publication No. 10-2011-0030474 uses a digital data compression technology, but the present invention uses a data scaling technology to very simply process a digital signal.